Tag: Domestication

That DNA link; from the BBC.

Another article about the origin of the dog.

This time on the BBC News website.

When I published the post about the dog’s nose and heart I concluded at the end that:

When one quietly reflects on the span of time that dogs and humans have been together, something in the order of 40,000 years, it’s no surprise that dogs have evolved to be our closest companion.

But the BBC proclaimed that:

The analysis reveals that dog domestication can be traced back 11,000 years, to the end of the last Ice Age.

So that rather confused me.

But read the full article from the BBC before I comment further.

ooOOoo

Dogs are humans’ oldest companions, DNA shows

By Paul Rincon
Science editor, BBC News website, 29th October, 2020

A study of dog DNA has shown that our “best friend” in the animal world may also be our oldest one.

The analysis reveals that dog domestication can be traced back 11,000 years, to the end of the last Ice Age.

This confirms that dogs were domesticated before any other known species.

Our canine companions were widespread across the northern hemisphere at this time, and had already split into five different types.

Despite the expansion of European dogs during the colonial era, traces of these ancient indigenous breeds survive today in the Americas, Asia, Africa and Oceania.

The research fills in some of the gaps in the natural history of our close animal companions.

Dr Pontus Skoglund, co-author of the study and group leader of the Ancient Genomics laboratory at London’s Crick Institute, told BBC News: “Dogs are really unique in being this quite strange thing if you think about it, when all people were still hunter gatherers, they domesticate what is really a wild carnivore – wolves are pretty frightening in many parts of the world.

“The question of why did people do that? How did that come about? That’s what we’re ultimately interested in.”

To some extent, dog genetic patterns mirror human ones, because people took their animal companions with them when they moved. But there were also important differences.

The Rhodesian Ridgeback retains ancestry from an ancient African dog lineage

For example, early European dogs were initially diverse, appearing to originate from two very distinct populations, one related to Near Eastern dogs and another to Siberian dogs.

But at some point, perhaps after the onset of the Bronze Age, a single dog lineage spread widely and replaced all other dog populations on the continent. This pattern has no counterpart in the genetic patterns of people from Europe.

Anders Bergström, lead author and post-doctoral researcher at the Crick, said: “If we look back more than four or five thousand years ago, we can see that Europe was a very diverse place when it came to dogs. Although the European dogs we see today come in such an extraordinary array of shapes and forms, genetically they derive from only a very narrow subset of the diversity that used to exist.”

An international team analysed the whole genomes (the full complement of DNA in the nuclei of biological cells) of 27 ancient dog remains associated with a variety of archaeological cultures. They compared these to each other and to modern dogs.

The results reveal that breeds like the Rhodesian Ridgeback in southern Africa and the Chihuahua and Xoloitzcuintli in Mexico retain genetic traces of ancient indigenous dogs from the region.

The New Guinea singing dog is one representative of a lineage found in dogs across Asia and Oceania

The ancestry of dogs in East Asia is complex. Chinese breeds seem to derive some of their ancestry from animals like the Australian dingo and New Guinea singing dog, with the rest coming from Europe and dogs from the Russian steppe.

The New Guinea singing dog is so named because of its melodious howl, characterised by a sharp increase in pitch at the start.

Greger Larson, a co-author from the University of Oxford, said: “Dogs are our oldest and closest animal partner. Using DNA from ancient dogs is showing us just how far back our shared history goes and will ultimately help us understand when and where this deep relationship began.”

Dogs are thought to have evolved from wolves that ventured into human camps, perhaps sniffing around for food. As they were tamed, they could then have served humans as hunting companions or guards.

The results suggest all dogs derive from a single extinct wolf population – or perhaps a few very closely related ones. If there were multiple domestication events around the world, these other lineages did not contribute much DNA to later dogs.

Dr Skoglund said it was unclear when or where the initial domestication occurred. “Dog history has been so dynamic that you can’t really count on it still being there to readily read in their DNA. We really don’t know – that’s the fascinating thing about it.”

Many animals, such as cats, probably became our pets when humans settled down to farm a little over 6,000 years ago. Cats were probably useful for controlling pests such as mice, that were attracted by the waste generated by dense settlements. This places their domestication in cradles of agriculture such as the Near East.

“For dogs, it could almost have been anywhere: cold Siberia, the warm Near East, South-East Asia. All of these are possibilities in my mind,” Pontus Skoglund explained.

The findings have been published in the journal Science.

ooOOoo

Well back to that age thing!

I decided to review the Wikipedia page on the origin of dogs. At last the discrepancy became clear. The difference between divergence and domestication. (My emboldening.)

The genetic divergence between dogs and wolves occurred between 20,000–40,000 years ago, just before or during the Last Glacial Maximum[6][1] (20,000–27,000 years ago). This timespan represents the upper time-limit for the commencement of domestication because it is the time of divergence but not the time of domestication, which occurred later.[6][7] One of the most important transitions in human history was the domestication of animals, which began with the long-term association between wolves and hunter–gatherers more than 15,000 years ago.[4]

So that explains a great deal.

But it nevertheless remains the fact that they are our longest, dearest companion.

A scientific view of domestication.

Of our dogs, of course!

You may recall that back on the 15th of this month, I posted a Note to Readers that spoke about my need to be focused on the editing of my manuscript. Here’s part of that note:

Dear readers, we are talking hours of revisions that I need, and want, to make.

All of which is my way of saying that if my posts over the next couple of weeks more strongly lean on the republishing of other material then you will understand why. In all cases I will endeavour to republish articles that are likely to interest you, of course!

Late yesterday, I completed the many revisions to the manuscript recommended by Joni Wilson but still have more days of formatting changes ahead.

Thus another republication of an item, this time an article that appeared on the Smithsonian website.

ooOOoo

Domestication Seems to Have Made Dogs a Bit Dim

Thanks to their relationship with us, dogs are less adept at solving tricky puzzles than their wolf relatives

It's OK, buddy. We're here to help. (stelo/iStock)
It’s OK, buddy. We’re here to help. (stelo/iStock)

By Rachel Nuwer, smithsonian.com, September 15, 2015

Dogs are considered some of the most intelligent animals on the planet. Thanks to a relationship with humans that dates back tens of thousands of years, dogs can respond to emotions, recognize numerous words and be trained to follow commands.

Notably, these seemingly smart accomplishments all hinge on the partnership between our two species. Now, however, tests of canine problem-solving skills indicate that dogs rely on humans so much that we actually seem to be dumbing them down.

Most studies that investigate dog intelligence assume that certain interactions with humans are indicative of higher cognitive function. In one experiment, for example, dogs and human-socialized wolves were presented with a canine version of the Kobayashi Maru — an unopenable box that contained food.

When confronted with a difficult task, dogs often turn to us—their human masters—for guidance, indicating their puzzlement with a cock of the head and eyes that seem to implore for help. Indeed, the dogs in the study quickly gave up and simply stared at the nearest human. The wolves, on the other hand, sought out no such help and persisted at trying to solve the impossible puzzle on their own.

Researchers usually interpret such findings as a sign of dogs’ intelligence; the wolves kept trying to win the no-win scenario, while the dogs knew that humans could help out with tasks they themselves could not solve.

But depending on humans for help is not necessarily a cognitive asset, points out Monique Udell, an assistant professor of animal and rangeland sciences at Oregon State University.

If dogs only turn to humans when presented with an impossible task—not a solvable one—then their “look back” behavior would indeed be advantageous. On the other hand, if they simply throw their paws up at the slightest hint of cognitive challenge, then that could indicate “a conditioned inhibition of problem-solving behavior,” as Udell puts it. Like a child whose parents always give away the answers to homework, dogs may be overly reliant on us, she surmised.

To test this hypothesis, Udell presented ten pet dogs and ten human-socialized wolves with a solvable puzzle. Sausage was placed inside a sealed plastic tub with a lid that included a bit of rope. With some paw and mouth finagling, the lid could be opened.

She also included ten shelter dogs in the study, because past research shows that shelter dogs are initially less responsive to humans compared to established pets. These animals acted as a sort of intermediary between hyper-socialized dogs and wolves.

Crazy smart, like a wolf. (Kaphoto/iStock)
Crazy smart, like a wolf. (Kaphoto/iStock)

Udell presented the canines with the puzzle box both in the presence of humans—an owner, caretaker or familiar person—and without any person nearby. Each time, the animals had two minutes to figure out how to get at the sausage. Subjects that failed in both trials were given a third and final try in which they also received verbal encouragement from their human friend.

Udell’s findings, reported today in the journal Biology Letters, were telling. In the presence of humans, just one pet dog and none of the shelter dogs managed to open the box. Eight out of ten of the wolves, however, succeeded in enjoying the sausage treat inside.

Wolves also spent more time chipping away at the problem and more time staring at the box, as if working out how to open it. Both pet and shelter dogs, on the other hand, did the opposite—they gave up more quickly and stared at humans instead of the box, seemingly asking for help.

When humans were not around, the findings were similar—nearly all of the wolves figured out how to open the box, while just one shelter dog and no pet dogs succeeded. In the third and final trial, dogs that had failed in both of the prior tests performed a bit better when humans encouraged them.

With some human cheerleading, four of nine shelter animals and one of eight pet dogs opened the box, and all spent more time trying to open the box and looking at the box than they did when they were either alone or when their human friends remained silent.

Udell’s results indicate that dogs do seem to be overly dependent on us compared to their wild relatives, although the cause of this—whether biological, environmental or both—still needs to be worked out.

Lucky for pet pooches, however, we humans will no doubt always be there to help them navigate all of life’s tricky plastic containers.

ooOOoo

Read more here.

Picking up on that last sentence, luckily for us humans our dogs will always be there to help us in innumerable ways, especially giving us unconditional love.

 

Prof. Pat Shipman

Pat Shipman showing how animals were intimately involved in the development of early humans.

Yesterday’s fascinating post was predominately taken up by a long and deeply interesting essay by Prof. Pat Shipman, The Woof at the Door.

Today, I want to report further on Pat Shipman primarily by looking at her book The Animal Connection.

What makes us human?

Let me do no more than quote from page 259,

Domesticating animals provided a new sort of benefit.  They were living tools first and meat sources later, only when their useful lives were over or circumstances required.  The crucial importance of animal domestication in modern life shows that our relationship with animals selected for a set of communication skills and abilities to observe, draw conclusions and make connections among different observations that had been increasingly important since at least 2.6 million years ago.  The relationship between such skills and modern behaviors that characterize humanity is clear.

Prof. Shipman also confirms that the first domestication was of the dog at 32,000 years ago and goes on to say,

Other types of domestic animals provide enhanced protection for people, dwellings, stored crops, and other livestock.  Dogs and cats are the obvious examples, but herders have recently started touting llamas as guardians for flocks of sheep.

The domesticated carnivores also provide important assistance in hunting.  Dogs are better trackers than humans; they are faster runners, take larger prey, and will hunt with humans.  Cats hunt solitarily and are far superior to humans at catching rodents that can decimate crops or carry disease.  Dogs hunt with you; cats hunt for you; but both offer an advantage. (p.254)

As I said, it’s a fascinating book and one that is already reshaping my knowledge about the early evolution of man.  And in terms of reshaping knowledge about early man, do go across to Pat Shipman’s Blog, The Animal Connection.

You can read a full review with links to a number of book sellers here.  Let me close by using this praise for the book by Jeffrey Moussaieff Masson.  (Masson’s book Dogs Never Lie About Love is just a few feet from me as I write this, a deeply moving book for all dog lovers.)

This is what Jeffrey Masson wrote about The Animal Connection,

Pat Shipman has written one of the most important books on the human-animal connection ever.  One might even say it is the single most important book, possibly the only one, to look at our deep connection to animals over the entire evolutionary history of our species.

The oldest bond in the world!

This most beautiful of relationships

That of man and dog.

A number of items have crossed my screen that, together, present the most wonderful story of the intensity and length of the time that mankind has shared his life with the dog.

First is this piece from Anthropology.net from 2008 when this was big news.

A Possible Domestication Of Dogs During The Aurignacian: 31,700 Years Ago

Both Dienkes and John Hawks have shared news about the latest research on the domestication of dogs. The researchers analyze 117 skulls of prehistoric canids from sites in Belgium, Ukraine and Russia. They conclude that a 31,700 year old canid from Belgium is ‘clearly different from the recent wolves, resembling most closely the prehistoric dogs.’

The draft can be found in the Journal of Archaeological Science under the title, “Fossil dogs and wolves from Palaeolithic sites in Belgium, the Ukraine and Russia: osteometry, ancient DNA and stable isotopes.” If the dating, and phylogenetic analysis is correct, these remains makes them the oldest known remains of domesticated dog, pushing back domestication time by 17,700 years, since the second oldest known dog, found in Russia, dates to 14,000 years ago as explained by Carl Feagans.

Doral View of the Goyet Cave Dog (a) and wolf skulls (b & c)Doral View of the Goyet Cave Dog (a) and wolf skulls (b & c)

Prehistoric dogs are distinguished from both prehistoric and extant wolves in having a shorter and broader snout, relatively wider brain cases, and a general reduction in skull size. Palaeolithic dogs in the study conform to this pattern. The researchers extended their anatomical analysis to mtDNA and stable isotopes on the Belgian samples. All fossil samples yielded unique DNA sequences.

This is a fascinating article, read the rest of it here.

Next a further explanation of the history of the dog from About.com Archaeology:

Dog history is really the history of the partnership between dogs (Canis lupus familiaris) and humans. That partnership is based on human needs for help with herding and hunting, an early alarm system, and a source of food in addition to the companionship many of us today know and love. Dogs get companionship, protection and shelter, and a reliable food source out of the deal. But when this partnership first occurred is at the moment under some controversy.

Dog history has been studied recently using mitochondrial DNA, which suggests that wolves and dogs split into different species around 100,000 years ago; but whether humans had anything to do with that, no one really knows.

Just think about that – 100,000 years ago!  But even if one assumes that early man wasn’t linked to this species divergence, the hard evidence of dogs being special to man still goes back a very long way.  Continuing the piece above:

The oldest dog skull discovered to date is from Goyet Cave, Belgium. The Goyet cave collections (the site was excavated in the mid-19th century) were examined recently (Germonpré and colleagues, cited below) and a fossil canid skull was discovered among them. Although there is some confusion as to which level the skull came from, it has been direct-dated by AMS at 31,700 BP. The skull most closely represents prehistoric dogs, rather than wolves. The study examining the Goyet cave also identified what appears to be prehistoric dogs at Chauvet Cave (~26,000 bp) and Mezhirich in the Ukraine (ca 15,000 years BP), among others.

However, I am told that what the Goyet Cave skull represents is not a “domesticated dog” but rather a wolf in transition to a dog, and that the physical changes seen in the skulls (consisting primarily of the shortening of the snout) may have been driven by changes in diet, rather than specific selection of traits by humans. That transition in diet could well have been partly due to the beginnings of a relationship between humans and dogs, although the relationship might have been as tenuous as animals following human hunters to scavenge, rather like the behavior that is believed to have existed between humans and cats. You could argue that cats never have been domesticated, they just take advantage of the mice we attract

As they say, dogs have masters, cats have slaves! Millions of dog owners have a relationship with their dog that is close to spiritual, and that also isn’t new. Let’s read on:

A burial site in Germany called Bonn-Oberkassel has joint human and dog interments dated to 14,000 years ago. The earliest domesticated dog found in China is at the early Neolithic (7000-5800 BC) Jiahu site in Henan Province. European Mesolithic sites like Skateholm(5250-3700 BC) in Sweden have dog burials, proving the value of the furry beasts to hunter-gatherer settlements. Danger Cave in Utah is the earliest case of dog burial in the Americas, at about 11,000 years ago.

Haplotypes and Grey Wolves

A recent study led by Robert Wayne (vonHoldt et al., below) at UCLA and appearing in Nature in March 2010 reported that dogs appear to have a higher proportion of wolf haplotypes from grey wolves native to the Middle East. That suggests, contrary to earlier studies, that the middle east was the original location of domestication. What also showed up in this report was evidence for either a second Asian domestication or a later admixture with Chinese wolves.

Dog History: When Were Dogs Domesticated?

It seems clear that dog domestication was a long process, which started far longer ago than was believed even as recently as 2008. Based on evidence from Goyet and Chauvetcaves in Europe, the dog domestication process probably began as long ago as 30,000 years, although the oldest evidence for a broader relationship, a working relationship, is at the Bonn-Oberkassel site, 14,000 years ago. The story of dog domestication is still in transition itself.

14,000 years ago people buried a dog with a human!  That is so beautiful.

Finally, National Geographic have been showing a series on this wonderful relationship between man and dog.  Enjoy this introduction video.